﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace ConsoleApplication2
{

    public class Test1{
        public Test1()
        { }

        public bool isValidFileName(string fileName)
        {
            if(String.IsNullOrEmpty(fileName)){
                throw new ArgumentException("Filename should not be empty");
            }
            if (!fileName.EndsWith(".doc")){
                return false;
            }

            return true;
        }

        
    }
}
